An organic photoconductor (OPC) is one of the key components of an electrophotographic (EP) process employed in many printing devices. Its lifetime is limited by the occurrence of defects introduced by mechanical and electrical interactions between the organic photoconductor (OPC) and the printing environment. The appearance of these defects can be further accelerated by interactions between the OPC and printing solvent (e.g., an isoparaffinic-based imaging oil in the case of an electrophotographic printing process). An inherent mechanical weakness of an organic material causes that OPC is one of the most frequently replaced printer component, which deleteriously impacts overall printing cost and financial bottom line of the printing provider. This shortcoming is particularly critical in the case of high speed digital printing that relies on minimizing printing costs in order to successfully compete with the analog printing. Previous attempts of replacing the OPC with an inorganic photoconductor or coating OPC with a hard inorganic protective layer have mostly failed due to excessive cost, manufacturing problems or poor performance of the resulting product.
For example, attempts to improve the mechanical strength of the OPC surface region have relied on coating it with a layer of inorganic, “hard” material, such as carbon (diamond), silica, etc. The coating is usually produced via a sputtering or sol-gel process. However, the coating suffers from a number of problems, including adhesion to the OPC, damage caused to the OPC during deposition, and mechanical wear-out when extensively used, producing excessive amounts of particles. Several attempts of coating the OPC with polymerized materials (such as by sputtering or deposition from a solvent) have also failed due to OPC damage, poor adhesion or excessive electrical resistivity of the coating.